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Centrifuge experiments on olivine, chromite, and plagioclase aggregates saturated in basaltic liquid show evidence of viscous compaction by grain‐boundary diffusion‐controlled creep. The experiments confirm that the exponential dependence of shear viscosity on melt fraction, observed at low porosities in earlier shear deformation experiments, extends to sedimentary porosities. The compaction profiles are inconsistent with the porosity‐dependence commonly ascribed to viscosity in macroscopic compaction models, which underestimate the effect of matrix disaggregation and consequently overestimate the viscosities of crystal mushes by 1–2 orders of magnitude. The time to halve the porosity of natural olivine igneous sediments by compaction is estimated from the centrifuge experiments to be O(103)y. Half‐times for plagioclase and chromite layers are O(104–105)y, suggesting that such layers compact on magmatic time scales only if they are loaded by additional sedimentation. At conditions relevant to melt flow in asthenospheric settings and trans‐crustal magmatic systems, the bulk and shear viscosities inferred for olivine and plagioclase are O(1017)Pa s, 4 orders of magnitude less than inferred from earlier experimental studies of the diffusion creep rheology. The reduced viscosities imply time‐ and length‐scales for compaction processes that are substantially shorter than previously anticipated. Our analysis serendipitously reveals that the oft‐neglected solidity term of the Carman‐Kozeny porosity‐permeability relation is essential to prevent non‐physical behavior in models of cumulate compaction. Plain Language Summary: The weight of the rocks overlying partially molten regions of the Earth squeezes melt toward the surface. This process is usually limited by rock viscosity and because rock viscosities are extremely high it is not easily observed. We review three sets of experiments on common crustal and mantle minerals in which melt expulsion was accelerated in a centrifuge. The results are consistent with recent theoretical models for rock viscosity and suggest that melt expulsion is substantially faster than previously anticipated. Key Points: Experimental compaction profiles are consistent with a porosity‐weakening effect predicted for grain‐boundary controlled diffusion creepBulk viscosities for plagioclase and olivine aggregates are three orders of magnitude lower than reported from earlier experimentsExtrapolation to natural conditions indicates diffusion creep remains an efficient deformation mechanism in partially molten natural rocks [ABSTRACT FROM AUTHOR]

An overview of previous researches related to the problem of flow around a bluffbody, using experimental and numerical methods, is presented in the paper. Experimental investigation was performed by a laser doppler anemometer, measuring velocity components of the water flow around a smooth sphere, and a sphere with dimples in square channels. Measurement results in subcritical velocity flow field, velocity fluctuation components, lift, drag and pressure coefficients, and 2-D Reynolds stress at quasi-stationary flow are conducted using 1-D laser doppler anemometer probe. The obtained experimental results are compared with numerical simulations, which are performed using the ANSYS-CFX software. For the numerical simulations of quasi-steady-state flow, k-ω turbulent model was used, while for numerical simulation of unsteady fluid-flow and for the comparison of results related to the eddy structures, vortex shedding and Reynolds stresses, detached eddy simulation were used. Since the obtained results of experimental and numerical investigation of flow around smooth sphere and sphere with dimples showed good agreement, the considered flow problem was expanded by introducing the influence of a transverse magnetic field with a slight modification of the electrical conductivity of the working fluid. The other physical properties of the fluid remained the same, which also corresponds to realistically possible physical conditions. Numerical simulations were performed for three different values of Hartmann number and very small values of Reynolds magnetic number (inductionless approximation). Comparisons and analyzes of the results were made for the cases containing a magnetic field and those with an absence of a magnetic field. [ABSTRACT FROM AUTHOR]

The present paper deals with the introduction of Backlund transformations by extended Harry-Dym flow and with the aid of the extended version of the Riccati mapping method is obtained new solutions. Then, we give the Backlund transformation of the Schrodinger flow and obtain its the Bonnet surface. In finally, results obtained with the mathematical model are evaluated by applying to mathematica. [ABSTRACT FROM AUTHOR]

This paper outlines a comprehensive study of the fluid-flow in the presence of heat and mass transfer. The governing non-linear ODE are solved by means of the homotopy perturbation method. A comparison of the present solution is also made with the existing solution and excellent agreement is observed. The implementation of homotopy perturbation method proved to be extremely effective and highly suitable. The solution procedure explicitly elucidates the remarkable accuracy of the proposed algorithm. [ABSTRACT FROM AUTHOR]

This paper uses 2D and high-quality 3D seismic reflection data to assess the geometry and kinematics of the Samson Dome, offshore Norway, revising the implications of the new data to hydrocarbon exploration in the Barents Sea. The study area was divided into three (3) zones in terms of fault geometries and predominant strikes. Displacement-length (D-x) and Throw-depth (T-z) plots showed faults to consist of several segments that were later dip-linked. Interpreted faults were categorised into three families, with Type A comprising crestal faults, Type B representing large E-W faults, and Type C consisting of polygonal faults. The Samson Dome was formed in three major stages: a) a first stage recording buckling of the post-salt overburden and generation of radial faults; b) a second stage involving dissolution and collapse of the dome, causing subsidence of the overburden and linkage of initially isolated fault segments; and c) a final stage in which large fault segments were developed. Late Cretaceous faults strike predominantly to the NW, whereas NE-trending faults comprise Triassic structures that were reactivated in a later stage. Our work provides scarce evidence for the escape of hydrocarbons in the Samson Dome. In addition, fault analyses based on present-day stress distributions indicate a tendency for ‘locking’ of faults at depth, with the largest leakage factors occurring close to the surface. The Samson Dome is an analogue to salt structures in the Barents Sea where oil and gas exploration has occurred with varied degrees of success. [ABSTRACT FROM AUTHOR]

The Habanero Enhanced Geothermal System (EGS) in central Australia has been under development since 2002, with several deep (more than 4000 m) wells drilled to date into the high-heat-producing granites of the Big Lake Suite. Multiple hydraulic stimulations have been performed to improve the existing fracture permeability in the granite. Stimulation of the newly-drilled Habanero-4 well (H-4) was completed in late 2012, and micro-seismic data indicated an increase in total stimulated reservoir area to approximately 4 km 2 . Two well doublets have been tested, initially between Habanero-1 (H-1) and Habanero-3 (H-3), and more recently, between H-1 and H-4. Both doublets effectively operated as closed systems, and excluding short-term flow tests, all production fluids were re-injected into the reservoir at depth. Two inter-well tracer tests have been conducted: the first in 2008, and the most recent one in June 2013, which involved injecting 100 kg of 2,6-naphthalene-disulfonate (NDS) into H-1 to evaluate the hydraulic characteristics of the newly-created H-1/H-4 doublet. After correcting for flow hiatuses and non-steady-state flow conditions, tracer breakthrough in H-4 was observed after 6 days (compared to ∼4 days for the previous H-1/H-3 doublet), with peak breakthrough occurring after 17 days. Extrapolation of the breakthrough curve to late time indicates that approximately 60% of the tracer mass would eventually be recovered (vs. approximately 80% for the 2008 H-1/H-3 tracer test). This suggests that a large proportion of the tracer may lie trapped in the opposite end of the reservoir from H-4 and/or may have been lost to the far field. The calculated inter-well swept pore volume is approximately 31,000 m 3 , which is larger than that calculated for the H-1/H-3 doublet (∼20,000 m 3 ). A simple 2D TOUGH2 tracer model, with model geometry constructed based on the current conceptual understanding of the Habanero EGS system, demonstrates good agreement with the measured tracer returns in terms of timing of breakthrough in H-4, and observed tracer dispersion in the tail of the breakthrough curve. [ABSTRACT FROM AUTHOR]

Well-exposed eolian units of the Jurassic system on the Colorado Plateau including the Wingate Sandstone, show prominent color variations throughout southeastern Utah due to diagenetic changes that include precipitation and/or removal of iron oxide, clay, and carbonate cement. Spatially variable characteristic diagenetic changes suggest fluid-rock interactions through the sandstone. Distinctive spectral signatures of diagenetic minerals can be used to map diagenetic mineral variability and possibly fluid-flow pathways. The main objective of this work was to identify characteristic diagenetic minerals, and map their spatial variability from regional to outcrop scale in Wingate Sandstone exposures of Lisbon Valley, Utah. Laboratory reflectance spectroscopy analysis of the samples facilitated identification of diagnostic spectral characteristics of the common diagenetic minerals and their relative abundances between altered and unaltered Wingate Sandstone. Comparison of reflectance spectroscopy with satellite, airborne, and ground-based imaging spectroscopy data provided a method for mapping and evaluating spatial variations of diagenetic minerals. The Feature-oriented Principal Component Selection method was used on Advanced Spaceborne Thermal Emission and Reflection Radiometer data so as to map common mineral groups throughout the broader Wingate Sandstone exposure in the area. The Minimum Noise Fraction and Spectral Angle Mapper methods were applied on airborne HyMap and ground-based hyperspectral imaging data to identify and map mineralogical changes. The satellite and airborne data showed that out of 25.55 km 2 total exposure of Wingate Sandstone in Lisbon Valley, unaltered sandstone cover 12.55 km 2 , and altered sandstone cover 8.90 km 2 in the northwest flank and 5.09 km 2 in the southern flank of the anticline. The ground-based hyperspectral data demonstrated the ability to identify and map mineral assemblages with two-dimensional lateral continuity on near-vertical rock faces. The results showed that 39.71% of the scanned outcrop is bleached and 20.60% is unbleached while 6.33% remain unclassified, and 33.36% is masked-out as vegetation. The bleached and unbleached areas are alternating throughout the vertical face of the outcrop. The relative hematite abundance observed in the unbleached areas are somewhat symmetrical. This indicates fairly similar reaction intensities along the upper and lower reaction fronts observed in the vertical section. The distribution geometry and relative abundances of diagenetic minerals not only suggest multiple paths of fluid-flow in Wingate Sandstone but also provides some insight about relative direction of past fluid-flow. [ABSTRACT FROM AUTHOR]

Shale detachment zones, their influence on deformational style, and their internal mechanisms of deformation are an understudied aspect of fold-thrust belts. Properties such as deformational temperature, lithology, and mineralogy are often recognized as having a key influence on the rheology and deformational style of detachment zones and overlying fold-thrust belts. However, little work has been conducted on rock properties of known detachment zones. A recently described upper-level detachment zone in the exhumed Khao Khwang Fold-Thrust Belt of central Thailand provides an ideal natural laboratory for investigation of the deformation conditions of the detachment zone, and association with its complex deformational style. The low-grade metamorphic indicator illite crystallinty is used to broadly constrain deformational temperatures, while oxygen and carbon stable isotope analysis provides insight into fluid flow history and fluid-rock interaction. Illite crystallinity data indicate deep diagenetic, to low anchizonal conditions, and temperatures of ~ 160–210 °C in the shale detachment, interpreted as reflecting peak metamorphic conditions during the Triassic Indosinian Orogeny. No trend between the intensity (spacing, complexity) of structures and illite crystallinty is observed. However, shale shear zones of continuous-style deformation and inferred higher finite strain display uniformly higher illite crystallinty than surrounding packages of discontinuously faulted shales. We also note a positive association between total organic carbon content in the shales and the spacing and complexity of deformational structures. Data from limestones and syn-tectonic vein fills detail the history of fluid-rock interaction during early mesogenesis, through to orogenesis. The early covariant trend of increasingly negative δ 13 C and δ 18 O values is attributed to increasing burial, while a divergent orogenic trend of increasingly negative δ 18 O values is interpreted as the result of a loss of matrix permeability and interruption of fluid-rock re-equilibration. These hottest fluids were concentrated along large thrusts which facilitated fluid movement during orogenesis. [ABSTRACT FROM AUTHOR]

Abstract: During compressive events, deformation in sedimentary basins is mainly accommodated by thrust faulting and related fold growth. Thrust faults are generally rooted in the basement and may act as conduits or barriers for crustal fluid flow. Most of recent studies suggest that fluid flow through such discontinuities is not apparent and depends on the structural levels of the thrust within the fold-and-thrust belt. In order to constrain the paleofluid flow through the Jaca thrust-sheet-top basin (Paleogene southwest-Pyrenean fold-and-thrust belt) this study compares on different thrust faults located at different structural levels. The microstructures in the different fault zones studied are similar and consist of pervasive cleavage, calcite shear veins (SV1), extension veins (EV1) and late dilatation veins (EV3). In order to constrain the nature and the source of fluids involved in fluid-rock interactions within fault zones, a geochemical approach, based on oxygen and carbon stable isotope and trace element compositions of calcite from different vein generations and host rocks was adopted. The results suggest a high complexity in the paleohydrological behaviors of thrust faults providing evidence for a fluid-flow compartmentalization within the basin. Previous studies in the southern part of the Axial Zone (North of the Jaca basin) indicates a circulation of deep metamorphic water, probably derived from the Paleozoic basement, along fault zones related to the major basement Gavarnie thrust. In contrast, in northern part of the Jaca basin, the Monte Perdido thrust fault is affected by a closed hydrological fluid system involving formation water during its activity. The Jaca and Cotiella thrust faults, in turn, both located more to the south in the basin, are characterized by a composite fluid flow system. Indeed, stable isotope and trace element compositions of the first generations of calcite veins suggest a relatively closed paleohydrological system, whereas the late calcite vein generations, which are probably associated with the late tectonic activity of the basin, support a contribution of both meteoric and marine waters. Based on these results, a schematic fluid-flow model is presented. This model allows visualization of three main fluid flow compartments along a N–S transect. [Copyright &y& Elsevier]

Abstract: The extraction and stripping of silver ions by hollow fiber supported liquid membrane (HFSLM) was examined. Pharmaceutical wastewater containing 30mg/dm3 of silver ions was used as the feed solution. LIX 84-I dissolved in kerosene, and sodium thiosulfate pentahydrate solution were used as the liquid membrane and stripping solution, respectively. The influences of several variables on the extraction and stripping of silver ions were investigated. Fluid-flow models for greater accuracy in describing the transport of silver ions from feed phase to stripping phase were developed. The models were calculated by linear algebra. The investigated parameters in the models were axial convections and axial diffusions on both sides, chemical reactions at the feed-liquid membrane and liquid membrane-stripping interfaces as well as the accumulation of silver ions in the system. The mass transfer coefficient in the liquid membrane (k m) was determined for use in the models. The final predicted concentrations of silver ions in feed and stripping phases were successfully in agreement with the experimental data. It indicates that the fluid-flow model can accurately estimate the transport of silver ions inside and outside the hollow fibers corresponding to the axial convections, axial diffusions, reactions at the feed-liquid membrane and liquid membrane-stripping interfaces. In accordance with this investigation, the HFSLM shows a practical implication for the use in pharmaceutical wastewater treatment. [Copyright &y& Elsevier]

Petroleum systems analysis has been carried out to better understand the geological CO2storage potential of the Gippsland Basin. From a regional perspective, the hydrocarbon migration architecture of the basin is interpreted to be dominated by two highly connected, filled-to-spill, hydrocarbon fairways; the northern (gas-dominated) and southern (oil-dominated) fill-spill chains, forming a convergent system that extends onshore along the Golden Beach Fill-Spill Chain (GBFSC). A separate oil-dominated Fill-Spill Chain, the Dolphin-Perch Fill-Spill Chain (DPFSC), is identified offshore to the southwest. Two broad flanking provinces, the Northerly Migration Province (NMP) and Southerly Migration Province (SMP), are also identified. Both provinces have broadly ramp-like geometries and relatively low dips. Migration across these provinces is not focused, and hence multiple pathways are present across a wide area. An understanding of the hydrocarbon systems in the basin can be used for characterising the potential for CO2storage. Previous studies have shown that the top seal potential of the offshore Gippsland Basin is suited to geological carbon storage and that large areas are prospective as storage regions. However, the linked nature of the fluid flow systems and the focused fluid flow fairways between areas of high storage potential and leaky systems onshore will require both a good regional geological understanding and informed resource management. [ABSTRACT FROM PUBLISHER]

Abstract: A coupled fluid-flow and geomechanics model for simulating coalbed methane (CBM) recovery is presented. In the model, the fluid-flow process is simulated with a triple-porosity/dual-permeability model, and the coupling effects of effective stress and micro-pore swelling/shrinkage are modeled with the coupled fluid-flow and geomechanical deformation approach. The mathematical model is implemented with a finite volume method. First, a case without considering coupling between fluid-flow and geomechanics is simulated and compared with an existing simulator. The effects of coupled fluid-flow and geomechanics are then studied in detail with two illustrative examples. The first one is designed for testing the effective stress effect without micro-pore swelling/shrinkage effect, and the other for testing the coupling effects of the effective stress and micro-pore swelling/shrinkage on the methane production. The numerical results indicate that both the effective stress and the micro-pore shrinkage make a significant contribution to fluid-flow in CBM reservoir and to methane production. The methane production sensitivity to Young’s modulus and Langmuir sorption strain are investigated as well. Finally, we make a dynamic analysis of the coupling effects of fluid-flow process and geomechanics. [ABSTRACT FROM AUTHOR]

Two chalk data sets from the Central North Sea (UK/Norway and Denmark) with a similar lithological classification and porosity values (5–20%) have a difference in permeability of up to three orders of magnitude. The method of measuring permeability was different for the two data sets: samples from UK/Norway were measured by transient pulse decay (TPD), while the Danish samples were measured by routine core analysis. Petrological and petrophysical characterization of samples from the two data sets have revealed that all samples display a similar range of rock properties; the differences are not due to regional facies variations. It is likely that the low permeability values reported by TPD have more validity than routine core analyses in measuring lower porosity and permeability chalk (5–20% porosity, <0.01 mD). The fact that large sections of North Sea chalk potentially have much lower permeability than previously reported has widespread implications for petroleum migration and entrapment, and overpressure generation. [ABSTRACT FROM AUTHOR]

3D numerical models of coupled deformation and fluid flow provide a useful tool for exploration in orogenic-gold systems. Numerical modelling of ore-forming processes can lead to a reduction in targeting and detection risk, thus improving the value proposition of mineral exploration. Hydrothermal mineralisation arises from a complex interplay of deformation, fluid flow, conductive and advective heat transport, solute transport and chemical reactions. Coupled simulation of all of these processes represents a significant computational challenge that cannot be solved within the time-scale of a mineral exploration program. However, the problem can be simplified by identifying a subset of processes representing the first-order controls on mineralisation at the scale of interest. For most orogenic-gold systems, it is argued that the first-order controls on mineralisation at the camp to deposit scale are deformation-induced dilation, fluid flow and fluid focusing. Hence, numerical models of coupled deformation and fluid flow can provide a quantitative insight into the localisation of ore-forming fluids in this type of system. In two case studies, known deposits were modelled in order to determine the critical deformation and fluid-flow-related factors controlling the localisation of mineralisation in these systems. The quantitative results from the forward models were then used as a basis for constructing predictive models that were applied to regional targeting, prospect ranking and selecting the choice of detection methods. Both case studies show that numerical modelling is capable of reproducing the distribution of known anomalism, and that it can predict anomalies that were not expected or accounted for by purely empirical analysis. [ABSTRACT FROM AUTHOR]

Abstract: Late Permian coals and coal measures in the Bowen Basin, Australia, are extensively mineralised with carbonates as cleat fillings and veins. The calcites in coal samples exhibit large variations in rare-earth element (REE) patterns and Sm–Nd ratios with some superchondritic values. Samples enriched in heavy REE (HREE) relative to light REE (LREE) define an Sm–Nd isochron corresponding to an age of 235±15 Ma, which is consistent with the timing of final contractional phase of the Hunter–Bowen orogeny. The corresponding initial εNd is +1.2 combined with HREE-enriched patterns suggests significant fluid interaction with primitive source rocks, which are consistent with arc-related volcanogenic sediments in the basin. Calcites characterised by HREE depletion relative to LREE are not in Sm–Nd isotopic equilibrium with the former samples that is interpreted to be due to the effect of a later hydrothermal event during the Late Triassic–Early Jurassic. Vein calcites in mudrocks from the coal measures display more pronounced HREE depletion and significant positive EuCN anomalies, which is related to the later hydrothermal event. REE distributions, together with the basin burial history, suggest that physico-chemical environments of fluid-flow events during the two separate major tectonic regimes were significantly different. This study shows that a combined application of Sm–Nd dating and REE geochemical tracing of authigenic carbonate minerals is very useful to constrain the evolution of multiple fluid-flow events in a sedimentary basin with a complex history. [Copyright &y& Elsevier]

The strong correlation between a bone's architectural properties and the mechanical forces that it experiences has long been attributed to the existence of a cell that not only detects mechanical load but also structurally adapts the bone matrix to counter it. One of the most likely cellular candidates for such a ‘mechanostat’ is the osteocyte, which resides within the mineralized bone matrix and is perfectly situated to detect mechanically induced signals. However, as osteocytes can neither form nor resorb bone, it has been hypothesized that they orchestrate mechanically induced bone remodeling by coordinating the actions of cells residing on the bone surface, such as osteoblasts. To investigate this hypothesis, we developed a novel osteocyte-osteoblast coculture model that mimics in vivo systems by permitting us to expose osteocytes to physiological levels of fluid shear while shielding osteoblasts from it. Our results show that osteocytes exposed to a fluid shear rate of 4.4 dyn/cm² rapidly increase the alkaline phosphatase activity of the shielded osteoblasts and that osteocytic-osteoblastic physical contact is a prerequisite. Furthermore, both functional gap junctional intercellular communication and the mitogen-activated protein kinase, extracellular signal-regulated kinase 1/2 signaling pathway are essential components in the osteoblastic response to osteocyte communicated mechanical signals. By utilizing other nonosteocytic coculture models, we also show that the ability to mediate osteoblastic alkaline phosphatase levels in response to the application of fluid shear is a phenomena unique to osteocytes and is not reproduced by other mesenchymal cell types. [ABSTRACT FROM AUTHOR]

Abstract: Samples collected from the Upper Ordovician Red River carbonates in a well at the centre of the Williston Basin revealed two paleomagnetic components with different inclinations, 60.3±3.9° (k =70.7, N =12) and 20.4±3.3° (k =141.2, N =8), but similar declination values in individual specimens. Inclination-only analysis indicates two possible scenarios for the age of these two magnetizations: in scenario (a) the timing of magnetization happened sometime between Late Ordovician to Devonian; and in scenario (b) there are two different remagnetizations, one that overlaps Pennsylvanian to Permian time while the other can have either a Late Jurassic or a Tertiary age. Whereas dolomitization and some isotopic data tend to support scenario (a), previous paleomagnetic data from the Williston Basin and from younger units in the same well, the tectonic evolution of the basin, and the hydrocarbon maturation pattern in the Red River carbonates all favour chemical remagnetization(s) driven by orogenic fluids during the Alleghenian and Laramide orogenies. [Copyright &y& Elsevier]

Abstract: We present 3-D deformation–fluid-flow numerical models which place constraints on the importance of basalt dome shape and syn-mineralising shortening direction in localising structurally controlled gold mineralisation around basalt domes near Stawell, Victoria, Australia. Gold mineralisation in the Magdala ore-body at the Stawell Mine occurs predominantly within a thin altered unit named the Magdala Facies which blankets the basalt domes. In numerical models of the Magdala Dome models only the east–northeast–west–northwest and east–west shortened models record high fluid-flow rates in areas of known mineralisation which is consistent with the syn-mineralisation shortening directions. In models of the Kewell Dome (a prospect to the north), the position of areas of high fluid-flow rate when shortened in the east–northeast–west–northwest and east–west direction, combined with information from limited drilling indicated the potential for gold mineralisation at the south-west end of the dome. Diamond drill holes in this area yielded significant gold values. [Copyright &y& Elsevier]

An analysis of the time-dependent evolution of the canonical Markov modulated fluid flow model is presented using elementary level-crossing arguments. [ABSTRACT FROM AUTHOR]

Markovian fluid flow models are used extensively in performance analysis of communication networks. They are also instances of Markov reward models that find applications in several areas like storage theory, insurance risk and financial models, and inventory control. This paper deals with the transient (time dependent) analysis of such models. Given a Markovian fluid flow, we construct on the same probability space a sequence of queues that are stochastically coupled to the fluid flow in the sense that at certain selected random epochs, the distribution of the fluid level and the phase (the state of the modulating Markov chain) is identical to that of the work in the queue and the phase. The fluid flow is realized as a stochastic process limit of the processes of work in the system for the queues, and the latter are analyzed using the matrix-geometric method. These in turn provide the needed characterization of transient results for the fluid model. [ABSTRACT FROM AUTHOR]

We examine the geochemical signature and structure of the Keno fault zone to test its impact on the flow of ore-mineralizing fluids, and use the mined exposures to evaluate structures and processes associated with normal fault development. The fault is a moderately dipping normal-fault zone in siltstone and silty limestone with 55–100 m of dip-slip displacement in north-central Nevada. Across-strike exposures up to 180 m long, 65 m of down-dip exposure and 350 m of along-strike exposure allow us to determine how faults, fractures, and fluids interact within mixed-lithology carbonate-dominated sedimentary rocks. The fault changes character along strike from a single clay-rich slip plane 10–20 mm thick at the northern exposure to numerous hydrocarbon-bearing, calcite-filled, nearly vertical slip planes in a zone 15 m wide at the southern exposure. The hanging wall and footwall are intensely fractured but fracture densities do not vary markedly with distance from the fault. Fault slip varies from pure dip-slip to nearly pure strike-slip, which suggests that either slip orientations may vary on faults in single slip events, or stress variations over the history of the fault caused slip vector variations. Whole-rock major, minor, and trace element analyses indicate that Au, Sb, and As are in general associated with the fault zone, suggesting that Au- and silica-bearing fluids migrated along the fault to replace carbonate in the footwall and adjacent hanging wall rocks. Subsequent fault slip was associated with barite and calcite and hydrocarbon-bearing fluids deposited at the southern end of the fault. No correlation exists at the meter or tens of meter scale between mineralization patterns and fracture density.We suggest that the fault was a combined conduit-barrier system in which the fault provides a critical connection between the fluid sources and fractures that formed before and during faulting. During the waning stages of deposit formation, the fault behaved as a localized conduit to hydrocarbon-bearing calcite veins. The results of this study show that fault-zone character may change dramatically over short, deposit- or reservoir-scale distances. The presence of damage zones may not be well correlated at the fine scale with geochemically defined regions of the fault, even though a gross spatial correlation may exist. [Copyright &y& Elsevier]